Maya Conserve attribute equivalent in Houdini?

[hkspowers]

Is there an equivalent node in Houdini to Maya's conserve attribute? I am trying to limit how high my particles bounce when they collide with a ground plane. The just bounce the same height infinitely. I want them to lose energy on each bounce. Any help would be greatly appreciated.

James

[Jason]

Is there an equivalent node in Houdini to Maya's conserve attribute? I am trying to limit how high my particles bounce when they collide with a ground plane. The just bounce the same height infinitely. I want them to lose energy on each bounce. Any help would be greatly appreciated.

James

The Collision POP and Limit POP have Gain Normal and Gain Tangent fields which are 1 by default. Make these values lower for less bounce.

Hope this helps!

Jason

[hkspowers]

The Collision POP and Limit POP have Gain Normal and Gain Tangent fields which are 1 by default. Make these values lower for less bounce.

Hope this helps!

Jason

Thanks a lot, this is perfect!

[Netvudu]

Not that you asked for it, but if you base your gain normal or gain tangents on a rand($ID) function you will get different random bounces for each particle, which looks more "organic". If you want to control this random values a fit( ) (or even better fit01( ) )expression will make wonders.

Edited May 6, 2008 by Netvudu

[DocWhite]

Not that you asked for it, but if you base your gain normal or gain tangents on a rand($ID) function you will get different random bounces for each particle, which looks more "organic". If you want to control this random values a fit( ) (or even better fit01( ) )expression will make wonders.

Thanks it worked. But some of them bounce infinitely, they stay like vibrating, is there any way to prevent that from happening? Thanks.

[Netvudu]

As usual with Houdini there are several ways.

You could create a spare parameter which multiplies those bounce values, and then animate that parameter either with keyframes or if you prefer an expression you could go for something along the lines of fit($FEND-$F,$FEND,0,1,0).

Other plausible alternatives could be an animated drag parameter, or an animated Velocity which simply "force-stops" the particles.

And there´s always VOPs...

Edited November 26, 2013 by Netvudu